The present invention relates to an airbag mounted on a high-speed movable means, such as automobile, to deploy in case of emergency, such as collision, to protect a driver or passenger, and more specifically, to an airbag provided with a tether and a flow adjustment member therein.
An airbag apparatus mounted on a vehicle inflates or deploys an airbag rapidly by gas pressure discharged from a gas generator called an inflator to protect the passenger in case of emergency, such as vehicle collision or the like.
Such an airbag apparatus may be provided with a flow adjustment member for guiding gas into the airbag in order to reduce the speed of the airbag projecting toward the passenger and to inflate and deploy the airbag rapidly in the vertical or lateral direction when the inflator is actuated.
It is also well known to provide a tether connecting a front portion and a rear portion of the airbag to prevent excessive projection of the front portion of the airbag.
In WO97/36768, an airbag provided with a distributing member and a tether therein is disclosed, wherein the tether is disposed at a position away from a gas flow ejecting from the distributing member so that the gas flow from the distributing member is not blocked by the tether.
In the airbag disclosed in WO97/36768 described above, since gas ejected from the distributing member simply goes straight toward the outer periphery of the airbag, the airbag is inflated unevenly toward the gas ejecting direction.
It is an object of the present invention to provide an improved airbag comprising a tether and a flow adjustment member, in which uneven inflation toward a specific direction is prevented and well-balanced inflation as a whole is ensured.
In the present invention, an airbag comprises an airbag body having a front surface facing a driver or passenger and a rear surface on the opposite side of the front surf ace, the rear surface having an opening for an inflator, a flow adjustment member disposed in the airbag body on the rear surface side and having an outlet port for discharging gas toward the outer periphery of the airbag body, and a tether connecting the front surface and the rear surface of the airbag body. The tether is disposed so as to face the outlet port in the state where the airbag body is inflated.
In such an airbag, gas ejected from the flow adjustment member does not flow straight, but changes the flowing direction by impinging upon the tether. In the course of inflation, the gas ejected from the flow adjustment member pushes the tether toward the periphery of the airbag body, and thus the tether is not tensed and the speed of the airbag projecting toward the passenger is reduced. In this way, the airbag can be inflated evenly as a whole.
one or more tethers may be provided. It is also possible to provide a gas passage, such as an opening or a slit, at the rear portion of the tether, so that dispersion of gas is adjusted. The gas passage may be an opening or a slit. The slit may have various configurations, such as a straight line or a cross-shape.
The tether may have a width that can cover the entire or almost entire outlet port of the flow adjustment member, or a smaller width.
The tether may have a widened portion at the rear portion thereof for receiving gas discharged from the outlet port of the flow adjustment member. In this arrangement, the tether is strongly pressed by the gas ejected from the flow adjustment member, thereby further reducing the speed of the airbag projecting toward the passenger.
It is also applicable to provide a base sheet that takes the position facing the outlet port of the flow adjustment member when the airbag is inflated and to provide the tether continuing into the base seat.
The number of the outlet ports of the flow adjustment member may be optional but one or more. Some of the outlet ports may be oriented toward the front of the airbag. The flow adjustment member may be for example a cylindrical shape, but it is not limited thereto.